CCL: SCF convergence problem with M06L functional in Gaussian 09

 Sent to CCL by: "Bulumoni  Kalita" [bulumoni(~)]
 Dear Users,
     My observations regarding the Pd4 calculations:
 1) In my job input, it was by mistake um06l.  But for such a system
 (multiplicity=1), restricted and unrestricted calculations give the same
 2) It completes very fast (27 SCF cycles) with b3lyp as said by Robert Molt.
 But with m06l, it takes long time (exceptionally long).  Here, one SCF Done
 takes 129 cycles and the other ~30.  And the calculations keeps on oscillating
 between these two values for quite long time. Moreover, for higher
 multiplicities, normally calculations are more time consuming.
 Now, I understand that for the above different situations, the initial guesses
 may be very different.  But, how to check and confirm that the initial guess is
 not too far from the expected one so that the SCF calculations take less number
 of cycles as well as the calculation for such a small molecules completes
 successfully soon.